Turner syndrome

Abstract

Turner syndrome (TS) or monosomy X, is the most common cause of hypergonadotropic hypogonadism in girls and young women. This chapter reviews the prevalence and different presentations of the syndrome and explains its chromosomal origins. The interpretation of chromosomal studies in diagnosis of and prognosis for TS, including prenatal testing, is reviewed. The most recent data on the TS phenotypic spectrum indicate ∼95% have short stature and ∼95% have primary ovarian failure, most presenting with primary amenorrhea but a significant number is present with 2° amenorrhea. Recent studies indicate that dysmorphic features are less common than previously described but complex cardiovascular defects and metabolic problems including osteoporosis, thyroid dysfunction, diabetes, and dyslipidemia are more common than previously appreciated. A significant proportion of young girls may have viable ovarian follicles with 15-20% experiencing spontaneous puberty, and 3-5% may achieve natural pregnancy. Spontaneous and assisted pregnancies with donated oocytes are associated with serious maternal complications, including eclampsia, diabetes, and catastrophic aortic dissections in women with TS. Thus, all TS women contemplating pregnancy need thorough medical and especially cardiologic evaluations and counseling as to the risks involved. Protocols for the physiologic induction of puberty and for the maintenance of feminization and prevention of osteoporosis in adults are described. The experience of premature ovarian failure and infertility leads to impaired psychosocial and sexual functioning in many women with TS. More attention focused on the psychological aspects of premature ovarian failure may help them cope with the diagnosis in a more positive manner. © Springer Science+Business Media, LLC 2010.